Nut Grass: A Deceptive Weed

Killing weeds and protecting the soil structure with landscape fabric.

There are two weeds in my plot that resist my technique of using black tarp to cover the beds for several weeks after preparing the soil. They are Yellow Nutsedge (Cyperus esculentus) and Field Bindweed (Convolvulus arvensis—which I’ll talk about another day), and both have strong nutrient storage mechanisms that can keep them alive for a long time, even without light and photosynthesis.

I took a picture of the Cyperus esculentus (which I grew up calling Nut Grass) to show you the structure of this unusual weed. It has a tiny, fragile, tap root that tethers it to the tuber. If you simply tug on the weed, that slender root will break, and because you have what looks like a complete plant, roots and all, in your hand, you may be tempted to think you’ve eradicated the pest. But, not so! That little nut is sitting safely down there waiting for another day to sprout again in hopes that the gardener may not be as vigilant next time.

Before I spend this entire article dissing this pesky plant, I should mention that Nut Grass is also an important food crop in some parts of the world. It’s “nuts” (the small tubers at the bottom of each plant) can be harvested, dried, and eaten. In Spain, they are the basis of a sweet, nutty milk called horchata. Wikipedia says that evidence exists for the cultivation of Cyperus esculentus in Egypt as far back as the sixth millennium BC!

The bed is (almost) weed free after three weeks of occultation.

In any case, the other day I pulled back the tarp I had been using to protect a bed that I had prepared several weeks earlier. The soil was amazing, and virtually weed free, except for that cluster of yellow, grass like sprouts, determined to survive. This was the ideal opportunity to invest a few minutes of surgical work in order to be rid of these weeds for good.

The soil in the newly uncovered bed was so soft and friable that my trowel slid effortlessly down to its full depth beside each shoot. With a gentle prying motion, I lifted the plant, complete with the little umbilical tether attaching it to its nut 6 to 8 inches below the surface. As I worked, I collected the weeds in a bucket so that I could dispose of them far away from my plot. They probably wouldn’t survive a good drying out in the hot sun, but I didn’t want to take any chances. Maybe next time I’ll take them home and eat them, instead!

Proteknet tunnels keep Japanese beetles, cucumber beetles, and birds off beds of dry beans. In the foreground, Rio Zape, a pinto bean discovered in a Hopi cave, is noted for hints of chocolate in its flavor profile.

Photo Credit: Diane Garey

The “Little Easy Bean Project:” We’re participating in a program to preserve rare beans. The low tunnel provides insect protection to ensure the precious seeds reach maturity so they can be deposited back in the seed bank in the Fall.

Photo Credit: Diane Garey

Inside one of the bean tunnels: all is looking good!

Photo Credit: Diane Garey

A couple of everbearing strawberries have been planted at eye level as a “trap crop” to lure passers by who might otherwise be tempted to taste the premium Fairfax strawberries below!

Photo Credit: Diane Garey

The spinach bed has just had it’s last harvest, and will be quickly prepared for a new planting of winter storage carrots.